1. Field of the Invention
The invention relates to a process for the production of cyclopropanenitrile derivatives.
2. Background Art
2,2-Dimethylcyclopropanenitrile is an important intermediate product for the production of S-(+)-2,2-dimethylcyclopropanecarboxamide. The former compound is hydrolyzed to R,S-2,2-dimethylcyclopropanecarboxylic acid, the acid is converted by resolution of the racemates to the optically pure S-(+)-enantiomer, and the S-(+)-enantiomer is subsequently converted via acid chloride to S-(+)-2,2-dimethylcyclopropane-carboxamide (European Published Patent Application No. 093511). S-(+)-2,2-dimethylcyclopropanecarboxamide is used in turn as the initial material for the production of the dehydropeptidase inhibitor cilastatin, which in treatment is administered together with penem or carbapenem antibiotics to prevent the deactivation of the antibiotics by a renal dehydropeptidase in the kidneys (European Published Patent Application No. 048301).
Nelson et al., J. Am. Chem. Soc., Vol. 79, (1957), pages 3467 to 3469, describes a process for the production of 2,2-dialkylcyclopropanenitriles starting from 2,2-dialkyl-1,3-propanediols. The latter are converted with p-toluenesulfonyl chloride to the ditosylate derivatives and then are reacted with potassium cyanide to the 2,2-dialkylcyclopropanenitriles. A great drawback of this process is that large amounts of potassium tosylate accumulate for disposal as a waste product.